Can I throw out paper receipts after I scan them

Usually yes, but there is a standard to meet.

What the CRA accepts. Scanned images of paper receipts and source documents, kept in electronic form, are acceptable to the Canada Revenue Agency, and once a paper document has been imaged to the required standard you are allowed to dispose of the paper and keep the image as the permanent record. The image has to be an accurate, readable reproduction that shows the same information as the paper, produced and stored to the national standard the CRA references for electronic records (CAN/CGSB-72.34).

The catch. "Accurate and readable" is doing real work here. A blurry photo that cuts off the tax line or the date is not a faithful reproduction, and the CRA can also ask for your electronic records in a usable, common file format it can open. If a third party does your scanning, meeting the standard is still your responsibility.

Where TALISK_HQ fits. When you scan a receipt in TALISK_HQ it is stored against the expense, encrypted, at full capture. The retention period is a separate question: see how long do I have to keep my records. Whether your imaging setup meets the standard well enough to bin the originals is worth confirming with your accountant.